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91.
Raymond G. Goodwin Wenie S. Din Terri Davis-Smith Dirk M. Anderson Steven D. Gimpel Timothy A. Sato Charles R. Maliszewski Camilynn I. Brannan Neal G. Copeland Nancy A. Jenkins Terry Farrah Richard J. Armitage William C. Fanslow Craig A. Smith 《European journal of immunology》1993,23(10):2631-2641
4-1BB is an inducible T cell antigen that shows sequence homology to members of an emerging family of cytokine receptors, including those for tumor necrosis factor and nerve growth factor. To aid in the analysis of the function of 4-1BB we have utilized a soluble form of the molecule as a probe to identify and clone the gene which encodes its ligand. The ligand for 4-1BB is a type II membrane glycoprotein that has homology to tumor necrosis factor, lymphotoxin, and the ligands for CD40 and CD27, all of which are themselves ligands to receptors in this superfamily. The gene for 4-IBB is on mouse chromosome 4 and maps close to the p80 form of the tumor necrosis factor receptor as well as the gene for CD30. The gene for 4-IBB ligand maps to mouse chromosome 17, but considerably distal to the tumor necrosis factor and lymphotoxin genes. Interaction of 4-1BB with its ligand induces the proliferation of activated thymocytes and splenic T cells, a response which is mimicked on similar cell populations stimulated with an antibody to 4-1BB. 相似文献
92.
Teodoro WR Velosa AP Witzel SS Garippo AL Farhat C Parra ER Sonohara S Capelozzi VL Yoshinari NH 《Pathology, research and practice》2004,200(10):681-691
The pathogenesis of diffuse connective tissue diseases (DCTD) is still unknown and has been extensively studied regarding its autoimmunity aspects related to extracellular matrix (ECM) remodelling, with an emphasis on the collagens at the inflammatory site. The present paper describes the pulmonary architectural and repair/remodelling responses to injury after immunization of rabbits with human type V collagen. The animal model consisted of rabbits immunized with collagen mixed with Freund's adjuvant and sacrificed 7, 15, 30, 75, and 120 days after the first of four doses of antigen. Pulmonary architecture remodelling response was evaluated by histology, morphometry, and the immunofluorescence method, according to compartments of reference (parenchyma and interstitium) and injury: 1 inflammation (polymorphonuclear and mononuclear cells); 2-repair (fibrosis) and 3-ECM remodelling (collagen system). The results showed an intense inflammatory involvement of the pulmonary vascular and bronchiolar parenchyma, characterized by increased wall thickness in small arteries, infiltrations by pseudoeosinophils, and mononuclear cells. Progressive remodelling of the pulmonary ECM was characterized by collagen deposition in the septal and bronchovascular interstitium, especially in rabbits sacrifices at 75 and 120 days. The ECM remodelling process was not reproduced when rabbits were inoculated with collagen types I and III. We conclude that the model reproduces morphologic changes similar to those observed in many DCTD, encouraging realization of other experiments to gain a better understanding of the pathogenesis of these diseases. 相似文献
93.
利用互补于Ⅰ型脊髓灰质炎病毒VP1区的一对引物,扩增病毒核酸中约268bp的片段。产物经HaeⅢ、RsaⅠ、XbaⅠ三种限制性内切酶切割后,用2%琼脂糖凝胶电泳检测,观察各分离株与SabinⅠ型株酶切图谱的异同。在所检测的13株病毒分离株中,只有1株的酶切图谱与SabinⅠ型株的相同,为疫苗相关株,其它的12株均为野毒株。本实验的结果表明从不同地区、不同年份所得的Ⅰ型脊髓灰质炎病毒分离株的碱基组成是有差异的。 相似文献
94.
2型糖尿病患者血清von Willebrand因子变化与微血管并发症的关系 总被引:1,自引:0,他引:1
目的 :探讨 2型糖尿病患者的微血管内皮细胞功能损伤与微血管并发症之间的关系。方法 :从 3 3 4名 2型糖尿病患者中选择合并微血管并发症但未合并大血管并发症者 3 2人作为微血管并发症组 ,并选择年龄与之匹配的无大血管及微血管并发症 55人作为无并发症组 ,观察二组患者血清vonWillebrand因子 (vWF)水平 ,并与年龄相接近的正常对照组 ( 4 0例 )比较。结果 :血清vWF水平正常对照组 0 .92U± 0 .44U/ml;无并发症组 1.15U± 0 .42U /ml ;微血管并发症组 1.3 7U± 0 .44U/ml;三组之间均有显著性差异 (P <0 .0 5~ 0 .0 1)。多因素Logistic回归分析表明vWF、空腹血糖分别与糖尿病人是否合并微血管病变显著相关 (ExpB分别为 3 .0 2 3 ,1.3 3 7,P <0 .0 5~ 0 .0 1) ,以vWF为应变量的多元逐步回归分析表明年龄、糖尿病病程、甘油三酯分别与vWF呈显著独立正相关 (B =0 .53 ,0 .3 5,0 .2 9,P <0 .0 5~ 0 .0 1)。结论 :在糖尿病患者中存在不同程度的微血管内皮细胞的损伤 ,此变化随着微血管并发症的进展呈进行性加重。以vWF升高所反映的微血管内皮细胞损伤是一项值得临床推广的研究方法 相似文献
95.
Shen Yan Tang Yi Zhong Cancan Liang Peihong Huang XuefangZhou Haiyan Chen Honghui Liang Weiguo 《生物医学工程学杂志》2007,(1)
检测用猪II型胶原免疫新西兰大白兔的异种异体细胞免疫反应。用II型胶原免疫新西兰大白兔60 d,定期抽取血浆检测抗II型胶原抗体;第60 d取兔的外周血淋巴细胞、兔脾细胞、淋巴结分别分离淋巴细胞,进行体外二次II型胶原刺激,检测由此引起的反应性的细胞增殖规律。实验分为二组,第一组加入不同浓度植物血凝素(PHA)作阳性对照,并测定非特异性免疫;第二组加入不同浓度II型胶原,检测特异性免疫。正常兔的淋巴细胞在PHA剌激下发生增殖,但对II型胶原的第一次剌激不发生增殖,而免疫兔对PHA和II型胶原的剌激均能发生显著的增殖。表明异种II型胶原在一定浓度下,可以引起免疫兔的抗II型胶原抗体的升高,并可引起兔脾、外周血淋巴细胞增殖,异种II型胶原能在体内引起细胞免疫反应。 相似文献
96.
97.
98.
Timothy W. Smith Jennifer L. O'Keeffe Kenneth D. Allred 《Journal of behavioral medicine》1989,12(1):1-11
The Framingham Type A Scale (FTAS) is one of three primary measures of Type A behavior. Unlike the structured interview (SI) and Jenkins Activity Survey (JAS), the FTAS is correlated with neuroticism. Further, neuroticism and FTAS scores predict angina-like chest pain complaints but not more definitive coronary heart disease (CHD) end points. Thus, the FTAS may be unique among Type A measures in its susceptibility to the neuroticism-symptom reporting confound. The present study examined associations of the SI, JAS, and FTAS with neuroticism and symptom reporting in two independent samples of undergraduate males. Unlike the SI and JAS, the FTAS was correlated with neuroticism and symptom reporting. Further, the correlations of FTAS scores and symptoms were due to shared variance with neuroticism. The findings are discussed in terms of a possible alternative interpretation of the Framingham Study and the need to consider neuroticism in studies of personality and health. 相似文献
99.
G. Feussner M. Eichinger R. Ziegler 《Journal of molecular medicine (Berlin, Germany)》1992,70(11):1027-1035
Summary Nineteen adult patients with type III hyperlipoproteinemia (HLP) and homozygosity for apolipoprotein (apo) E2 were treated with the 3-hydroxy-3-methyl glutaryl coenzyme A (HMG CoA) reductase inhibitor simvastatin (20 or 40 mg per day) alone or in combination with the fibrate derivative gemfibrozil (450 mg per day) during a 30-week outpatient study. With the 20-mg dose (n = 19) the mean plasma cholesterol level decreased from 13.24±8.04 8.04 at baseline to 8.04±4.19 mmol/l (mean reduction 39.3%; P<0.05), and the mean plasma triglyceride level decreased from 13.47±19.22 to 7.84±7.71 mmol/l (–41.8%; NS); this was due to a decrease in very low density lipoprotein (VLDL) cholesterol from 8.95±8.64 to 4.94±4.24mmo1/l (–44.8%; NS), a decrease in low density lipoprotein (LDL) cholesterol from 3.54±0.93to 2.25 ± 0.59 mmol/l (–36.5%; P<0.01), and an increase in high density lipoprotein (HDL) cholesterol from 0.72±0.28 to 0.85±0.34 (+18.1%; NS). Thirteen patients were treated with 40 mg simvastatin per day. Under this regimen there was a further significant decrease in LDL cholesterol from 2.33±0.62 to 1.81±0.49 mmol/l (–22.3%; P<0.01). In six patients who remained hyperlipidemic on monotherapy combination drug therapy with simvastatin (40 mg per day) and gemfibrozil (450 mg per day) was given. Compared to simvastatin alone the addition of gemfibrozil further lowered plasma concentrations of total cholesterol by 14.9%, VLDL cholesterol by 23.5%, and triglycerides by 17.1%, although this was not statistically significant. No patient was discontinued from single or combination drug therapy, and no severe clinical or biochemical side effects were observed. The results of this study demonstrate the usefulness of simvastatin in the therapy of type III HLP and indicate that in individual patients who remain hyperlipidemic on monotherapy combination drug therapy with both of these drugs is effective in further reducing plasma concentrations of total cholesterol, VLDL cholesterol, and triglycerides. Although no patient in this investigation developed myopathy or rhabdomyolysis, combined fibrate-HMG CoA reductase inhibitor treatment should be considered only for severe forms of hyperlipidemia and for patients who do not respond sufficiently to mon-therapy of any of these drugs.Abbreviations Apo
Apolipoprotein
- CPK
creatine phosphokinase
- GGT
gamma-glutamyl transpeptidase
- HDL
high density lipoproteins
- HLP
hyperlipoproteinemia
- HMG CoA
3-hydroxy-3-methyl glutaryl coenzyme A
- IDL
intermediate density lipoproteins
- LDL
low density lipoproteins
- TG
triglycerides
- VLDL
very low density lipoproteins 相似文献
100.
Ei Kawahara Yoshio Oda Shogo Katsuda Isao Nakanishi Kunihiko Aoyama Katsuro Tomita 《Virchows Archiv : an international journal of pathology》1991,419(5):373-380
Summary Thickened ligamenta flava obtained from 14 patients with spinal canal stenosis were examined with special reference to type VI collagen. The characteristic histological finding in the thickened area was rupture of normal elastic fibre meshwork with resultant fibrosis which usually appeared hyaline. Using an immunohistological method, collagen types VI, I and III were found to be present in the hyaline matrix. Ultrastructural study revealed many microfilamentous structures of type VI collagen admixed in loosely packed, banded collagen fibres. With differential salt precipitation of pepsin-extracted collagen the existence of type VI collagen was confirmed by SDS-polyacrylamide gel electrophoresis analysis and Western blotting analysis using anti-type VI collagen antibody. Quantification of type VI collagen in pepsin-extracted crude collagen samples by an inhibition enzyme-linked immunosorbent assay showed an increasing amount of type VI collagen in the thickened ligamenta flava compared to the normal ligaments. Thus, increase of type VI collagen is the main contribution to the thickening of the ligamentum flavum. This may represent an adaptational and reparative process associated with disruption of elastic fibres. 相似文献